Support nested objects in query params

[hwuethrich]

While trying to expose a moleculer-db service through the API gateway I noticed there is no way to pass the query param to the services list action (doc). The service expects the query param to be of type object but nested objects are not supported by node's querystring module (see nodejs/node-v0.x-archive#1665).

This PR replaces querystring with qs, which supports nested objects.

Example Request:
GET /users/list?query[name]=Peter

Before (using querystring module):
params: { "query[name]": "Peter" }

After (using qs module):
params: { "query": { "name": "Peter" }}

What do you think?

[coveralls]

Pull Request Test Coverage Report for Build 229

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 91.304%

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Totals
Change from base Build 225:	0.0%
Covered Lines:	412
Relevant Lines:	438

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💛 - Coveralls

[icebob]

Good idea, and nice PR with tests! Thanks!

[icebob]

Released in moleculer-web@0.7.0-beta4

[hwuethrich]

@icebob No problem! And thanks for the quick release! 😀